What is cloud computing? Cloud computing simply refers to a software and hardware that works as a service over the internet. This new way of computing allows clients to choose, manage, manipulate, share data or download without the need of software deployment and hardware maintenance. Cloud computing is built with lots and lots of hardware on a data centre somewhere overseas.

Cloud computing may be confused by web hosting because the similarity of their functionality, both accessible by a high-speed broadband connection and also uses servers to work. If you have your own website that has a feature that people interact and share, the effect is when a massive wave of data comes, it needs more drive space, your website tends to fail because lack of data storage. If you have a fixed size of storage, you're website probably at the moment encountering a problem. Thus, what you will do? Of course buy more servers; Web hosting gives you a portion of a server or a server itself, just waiting for you to use them whereas consuming power and space. Their differences lies on how much hardware computing capability, flexibility or scalability than web hosting can provide.

Cloud computing has an automatic feature that loads many servers only when needed. Servers combined and work together to fill up the computing power, and when data shrinks, servers are automatically released instantly; giving other web applications a space for a later use, so there's no need for you to buy a dedicated server. The effect of this is very economical, the lesser servers are used the lesser hardware to maintain, making the level of our carbon footprint to go down.

Building blocks of cloud computing:

1. Virtualization: servers should be virtualized so that end-users can share and manage virtualized servers. This technique is similar to Windows Virtual PC, software virtualization and hardware-assisted virtualization−the main key of cloud computing. Without this technology servers and storage, it will not allow you to share or distribute to other clients.

2. Infrastructure: Infrastructure as a Service or IaaS, Examples are; Amazon EC2 and Sun Grid. This service has the ability to choose the amount of computing capacity you need. If you want to build your own web applications and services, you can set the amount of disks space, network speed or connection speed that you require. And the good news about this, you only pay what you use, and anytime you can either increase or decrease the amount of computing power you need.

3. Platform: Platform as a Service or PaaS, Examples are; Google App Engine, Force.com and the famous Microsoft has also embraced this technology; they called it Windows Azure−a cloud computing platform.

4. Application: Software as a Service or SaaS, Examples are; Google Apps (Google docs, Google Reader), Peepel, and Zoho Writer. This known web applications mimics your license software installed on your computer by accessing them online.

Cloud computing are now popular for small and large business to cut the cost but still effective. Imagine this, in traditional license software, you bought an expensive car and have a license to drive it, and worst things will come, you have to maintain its engine, buy gasoline, and even buy car insurance. But with cloud computing, you don't have to buy actually a new car; it’s like renting a taxi cab with a meter, just pay on how far it will travels you, and when you’re done just get out of it. So why buy a new car if you can rent a car? Still works the same and you might not need it tomorrow, right?

So what is the issue of cloud computing facing right now? The fact that some industries don't want their important data out of their own box, they don't want the risk of security and privacy, while internet threats are just around the corner. A good encryption of data should be implemented first before they embrace this kind of technology.